Archive for September, 2009

Scientists have found another reason why the fizz in a glass of champagne is so important: Besides tickling the tongue and pleasing the eye, the bubbles also release aromatic compounds that they’ve dragged up from the liquid in the glass. A new study found that concentrations of certain chemical compounds are higher in the air just above the glass than in the actual champagne.

Wine expert Jamie Goode comments: “In the past, we thought that the carbon dioxide in the bubbles just gave the wine an acidic bite and a little tingle on the tongue, but this study shows that it is much more than this” [BBC News]. Smelling the chemical compounds enhances the overall flavor of the champagne, researchers say.

Once again, scientists are trying to read your mind. Specifically, they are using fMRI (functional magnetic resonance imaging) to see what areas of the brain people use to process numbers, and even to determine what number a person just viewed.

Test subjects were shown images with either an amount of something—in this case a bunch of dots—or a numeral like 2, 4, or 6. Scientists suspected that our brains use overlapping areas to process quantities and their symbolic representations, however the findings suggest that people process the fundamental idea of a quantity differently from the way they process a symbol representing that quantity [Science News]. When a test subject looked at two dots and later at the number 2, different areas of the brain were activated, researchers report in Current Biology.

The tiny island nation of Palau has taken a big step to protect the ocean’s endangered sharks, by designating all of its territorial waters a shark sanctuary within which all commercial shark fishing is prohibited. Palau’s president, Johnson Toriboing, announced the plan at a meeting of the UN General Assembly last Friday. Sharks are increasingly under threat as the demand for shark-fin soup—a delicacy in many Asian countries—has risen worldwide. “The need to save the ocean and save sharks far outweighs the need to enjoy bowls of soup,” Toriboing said [National Geographic News].

Palau consists of about 200 small islands in the Pacific Ocean to the east of the Philippines; its expansive marine territory spans 230,000 square miles, an area about the size of Texas. About 130 species of rare sharks either make their homes or pass through these waters, including hammerheads, leopard sharks, and reef sharks, as well as the related stingrays.

One day, the most advanced ships may not have steel hulls that slice cleanly through the water, but instead may sort of ooze along, leaving a wake of slime and microbes. Researchers are trying to design a ship that continuously exudes slime to form a coating around its hull that steadily wears away, taking hangers-on like barnacles with it.

Barnacles and the other sea creatures that accumulate on boats’ undersides create drag, and therefore reduce speed and energy-efficiency. The problem is an expensive one, as it requires vessels to be brought into dry dock every couple of years to remove plants and animals from the hull. It has been made worse by the banning last year of antifouling paints based on tributyltin, which is toxic to marine life [New Scientist].

A feathered dinosaur unearthed in a Chinese quarry has added another solid piece of evidence to the theory that birds descended from dinosaurs. The newly uncovered fossil of the species Anchiornis huxleyi dates from the Late Jurassic period, 151-161 million years ago, and therefore predates the earliest known bird, the Archaeopteryx. Paleontologists say this represents the final proof that dinosaurs were ancestral to birds. “Drawing the tree of life, it’s fairly obvious that feathers arose before Archaeopteryx appears in the fossil record” [BBC News], says paleontologist Michael Benton.

The creature, described in a paper [pdf] in Nature, was covered in the short feathers known as “dino-fuzz,” and had longer feathers on both its forelimbs and its back legs that formed primitive wings. The four-winged dinosaurs also had feathers on their feet and wing-like attachments on the arms and legs. But they could probably only glide, as their plumage was insufficient for powered flight [Nature News].

Science, September 25
The week’s biggest news: there’s water, water everywhere in our solar system, or at least on our moon and on Mars. First, a trioofstudies reported on the latest findings from the moon, where an Indian orbiter and two NASA probes detected the chemical signature of water all around the moon, not just in the permanently shadowed polar craters where scientists think ice might lurk. But researchers say the water isn’t sitting around in pools–it’s bound up with rocks and minerals in the top few millimeters of moon dust. In the Mars finding, researchers looked at five craters recently created by meteor impacts, and discovered that subterranean ice had been kicked up to the surface. The presence of ice on Mars wasn’t a surprise, but the quantity of it was–researchers say there may be ice sheets hundreds of miles across just beneath the surface.

Nature Neuroscience, October
Two papers in this journal upended expectations of who can learn, and what they can learn. In the first study, researchers found that coma patients in a completely unresponsive, vegetative state are nonetheless capable of the most basic kind of learning: Pavlovian conditioning. These patients learned to associate a noise with an unpleasant puff of air to their eye, and began blinking or twitching as soon as they heard the noise. The findings suggest that these patients may have a rudimentary level of consciousness that isn’t detected in other tests. In the second study, researchers trained paralyzed rats to walk again using a combination of treadmill exercise, drugs, and direct electrical stimulation of their nerves. Although the rats’ damaged spinal cords couldn’t convey a message from their brains to their legs, the spinal circuits could be coaxed into sending the messages to the legs, resulting in movement that was almost indistinguishable from normal walking.

Here’s yet another reason to get a good night’s rest: Researchers have found a link between the lack of sleep and the development of Alzheimer’s in mice.

The researchers studied levels of amyloid beta — a protein that accumulates in the brain of people with Alzheimer’s — in mice genetically engineered to have a version of Alzheimer’s disease. Amyloid levels rose in the brain when the mice were awake, and fell when they slept. When the researchers prevented the mice from sleeping, it made matters worse [Reuters]. Sleep deprivation accelerated the formation of plaques made of amyloid beta, they found.

The study, published in Science, may lead to other studies that examine whether people with chronic sleep problems are more likely to develop Alzheimer’s. Says lead researcher Jae-Eun Kang: “The hope would be to show that treating sleep problems in humans is important not just for the immediate effect of having a normal life, but also for the long-term effect of having a healthier brain” [Bloomberg].

Now that the first vaccines against swine flu are about to become available, scientists are busy working out the details of how the vaccines can best be administered. Researchers already knew that a single dose was sufficient to protect adults, and they’ve now found that one shot works for teenagers and children over the age of 10. But young children who have never had the flu or a flu shot, however, need two doses, they said…. Children 6 months to 9 years old received some protection from one shot, but not enough, so health officials will recommend that they get two shots 21 days apart [The New York Times].

At least 6 million doses of vaccine will be available the first week of October, federal health officials announced today, and this first batch is in the form of a nasal spray called FluMist. The intranasal vaccine has not been approved for children younger than 2, adults older than 49 or pregnant women, so it may go primarily to healthcare providers [Los Angeles Times]. Injectable vaccines should make it to doctors’ offices a week or two later.

New York State has taken the drastic step of requiring that all hospital, home health and hospice workers get the swine flu vaccine. Experts say the mandatory vaccination will protect not just the workers, but also their patients. But some workers are upset by the edict. Health workers’ union official Joel Shufro says the unions do not oppose vaccination “but we oppose a mandatory program,” he said. “This is: ‘You don’t get the shot, you’re fired’” [The New York Times].

Even European eels enjoy a trip to the Bahamas, for mating season of course. The eel travels thousands of miles to the Sargasso Sea, in the Atlantic Ocean near the Bahamas, just to get a little action. Scientists wanted to see what the little eels were up to on their trek, so they equipped a few with satellite tags and tracked their journey, which surfaced in Science this week. The tags allowed researchers to follow 22 eels for the first 1,300 kilometers of their trek from the coast of Ireland to mating grounds near the Bahamas. Understanding the details of the eels’ journey may help to protect this critically endangered species, a favorite of sushi eaters [Science News].

The tags recorded location, speed, depth and direction of the eels for 6 months, before popping off and floating to the ocean’s surface to beam their data back to the laboratory. The researchers found the eels swim too slowly to get to the Sargasso Sea by the April spawning period. The researchers suggest this means the eels may gain speed and travel efficiency by entering the ocean currents that begin west of Africa and continue as part of the subtropical gyre system that flows to the Caribbean [BBC News]. The data also show that the eels swim in shallow, warm water at night and dive to depths of 3,200 feet during the day swims. Since the eels do not feed on their trip, scientists think swimming in warm water boosts metabolism, while the cold water helps slow sexual development until they reach the Sargasso Sea.

Mars has quite a bit more water than previously thought, according to a new report in the journal Science. NASA said its Mars Reconnaissance Orbiter spotted ice at five new Martian craters, likely kicked up by meteor impacts [Reuters]. It’s no surprise that the NASA orbiter found water, it’s the size of the find—twice as much as in Greenland’s ice sheet—that surprised scientists. The ice is just under the surface, so it was only visible after the recent meteor impacts.

The ice was found half way between the north pole and the equator, which is the farthest south ice has been found on Mars. Scientists believe that water once flowed across the planet, but most thought the surface had been largely dry and parched, with planet-wide dust storms, for billions of years. They had long known that water ice and carbon dioxide ice accumulated at the poles in winter, but until now, they had no idea how far from the poles the underground ice sheet extended [Los Angeles Times].

This image shows two craters with blueish ice, which—when exposed to the Martian atmosphere—sublimates over the course of 15 weeks.